class_docstr: Cache stores downloaded objects, notably apache-rat.jar. 
docstr: Return the full path of a key if cached, None otherwise. 
docstr_tok: ["Return","the","full","path","of","a","key","if","cached",",","None","otherwise","."]
code: def get(self, key):
      """Return the full path of a key if cached, None otherwise."""
      path = self.key_path(key)
      return path if path.exists() else None
  
file_path: arrow/dev/archery/archery/utils/cache.py
imports: from pathlib import Path
  import os
  from urllib.request import urlopen
  from .logger import logger
label_desc: Use image node_id 3 for calling the Cache obj's underlying member method code with example usage: obj.get(key) and returns: unknown